Ments



C. F. BENNON.

GRIPPER.

APPLICATION FILED OCT. 4. 1915.

Patented June 3, 1919.

UNITED STATES PATENT OFFICE.

CHARLES FAWCET'I BENN ION, 0F LEICESTER, ENGLAND, ASSIGNOR, BY MESNE IASSIGN- MENTS, T0 UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY,

A CORPORATION OF NEW JERSEY.

GRIPPER. v

Patented June 3, 1919.

Application filed October 4, 1915. Serial No. 53,968.

To all whom it may concern:

Be it known that I, CHARLES F. BENNION, a subject of the King of England, residing at Leicester, Leicestershire, England, have invented certain Improvements in Grippers,

of which the following description, in con-' nection with the accompanying drawings, is aspecification, like reference characters on the drawings indicating like parts in the several figures.

This invention relatesfor example, as are used in pulling-over machines of the type shown and described in U. S. Letters Patent No. 1,029,387, granted on application of R. F. McFeely. In this type of machine as usually constructed each gripper comprises arigid jaw and a cooperative jaw pivoted relatively to the rigid jaw and arranged to swing toward the latter through different angles. of the gripping faces of the different jaws lie, therefore, at various angles to each other according to the thickness of the upper being seized, portions only of the gripping faces of the jaws are efficiently utilized in actually holding the upper, with the result that under some conditions when the upper is tensioned to grippers such about the last it tends to slip from between the jaws and is liable to become torn or damaged.

Objects of this invention are to provide a construction of gripper in which extending laterally of the gripper, and

mounted in said recess is a gripping member which is adjustable in response to engagement with the material about the axis of the curve of said wall. With this construction the material is gripped effectively by the cooperating gripping faces of the Since the planes jaws irrespective of the extent to which the jaws are permitted to close by the thickness of the material.

Another feature of the invention consists in anovel construction of gripper whereby the bite of the gripper upon the material'is increased by the the construction shown,'wherein one of the grlpper jaws carries a gripping member movable angularly relatively to the other aw independently of 'the relative opening or closing movements of the jaws, ping member is so mounted as to cause it to be forced toward the opposite jaw in response to the relative pull between the gripper and the material. In the particular construction shown the gripping member is seated in a, recess in the gripper jaw the bottom wallof which is curved about an axis which lies at which the gripping face of the member is located, and by reason of'this construction the pull upon the material tends to swing the gripping member bodily lengthwise of the embodied in a construction in which one of the gripper jaws comprises a gripping member angularly adjustable relatively to the other jaw, resides in novel yielding means for determining the normal position of the gripping member while permitting it toassume difierent-positions in response to engagement with the material.

Other objects and features of the present invention will be more fully explained in such grip:

the side of said member on the following description and then pointed V I out in the claims.

In the drawings: Figure l is a side elevation, with parts in longitudinal section of a gripper embodying the present invention. Fig. 2 is a front elevation of the movable aw.

Fig. 3 is a side elevation, with parts in longitudinal section, showing the positions of the several parts when the gripper is holding stock under tension.

The gripper supporting and controlling mechanism is. preferably substantially the same as that disclosed in the above-mentioned patent and includes a casing or carrier 2 which supports the two aws and contains the devices for operating them to grip and pull the stock. The jaw 3 is rigidly secured to the casing by a bolt 5 while the jaw 6 is pivoted on the pin 8 and has a tail piece 9 that is engaged by a roll 12 on a slide 13 for rocking the pivotal jaw 6 toward the cooperating jaw 3. upwardly through the casing and is connected with mechanism (not shown) by which the slide is operated for closing and raising the j aws.

As the jaw 6 swings about the pivot 8 toward the cooperating stationary jaw 3 the gripping face thereof, in constructions such as provided heretofore, assumes difierent angles relatively to the gripping face of the other jaw and differences in the thickness of different stock seized by the jaws causes corresponding variations in the angular relation of the gripping faces with the result that only a portion of the gripping faces of the jaws may be utilized for engaging the stock or may act with maximum eliiciency, the upper portion of the gripping faces being relatively ineflicient in seizing thin stock and the lowerportion of the gripping faces being less than normally efficient in seizing thick stock. 0

In the illustrative embodiment of this invention the inside face of the pivoted jaw 6 is provided with a concaved recess 15 the bottom wall of which is curved lengthwise of the gripper about an axis substantially parallel to the pivotal axis of the jaw 6, and a gripper plate 16, the outer face of which is roughened to correspond with the grip ping face of the rigid jaw, is loosely retained in this recess 15 by a spring plate 19. This spring plate is secured at one end to the jaw 6 by a screw 22 and has its opposite end bearing in a recess :23 in the toothed face of the gripper plate 16 against the gripper plate, thus retaining the plate in the recess while permitting sliding movement of the plate longitudinallyof the jaw and also returning the plate to a normal position when the jaws are opened. The gripper plate 16 thus seats upon the bottom wall of the recess 15 as a bearing, the axis of the curve of this wall lying at the side of the plate 16 on which the gripping face of the plate is located. Flanges 25 on either side of the jaw 6 prevent movement of the sliding plate transversely of the jaw. It will be seen that with this construction whatever thickness of stock is being seized by the jaws the gripping plate of the pivoted jaw may adjust itself by a bodily swinging movement longitudinally of the jaw into parallelism with the cooperatmg grlppmg The slide 13 projects.

face of the rigid jaw, thereby equalizing the gripping force between different parts of the gripping faces of the aws and utilizing the entire gripping surfaces of the jaws for securely holding the upper while it is being drafted about the last. After the jaws have seized the upper material and are actuated to tension the upper about the last the downward strain tending to pull the upper material out of the aws acts upon the gripping plate. 16 with a tendency to move it lengthwise of the jaws, whereby its outer edge portion is forced by the curvature of the recess toward the gripping face of the stationary jaw and thus bites the upper material with increasing force independently of the mechanism for closing the jaws upon the upper material.

Although the invention is shown and described herein with reference to a gripper particularly designed for use in a pullingover machine, it will be understood that the invention is not thus limited in its applicability but that the novel features are of general utility in grippersadapted for various kinds of work.

Having described 'a preferred embodiment of the invention, I claim as new and desire to secure by Letters Patent of the United States: v

1. In a pulling-over machine gripper, the combination with a rigid aw, of a jaw pivoted relatively to the rigid jaw to swing toward the latter through different angles for gripping upper materials of different thicknesses, said pivoted jaw having in its inner face a recess the bottom wall of which is concavely curved about an axis substantially parallel to the axis. of said pivoted jaw, a gripping plate mounted in said recess and movable therein about the axis of said curve into parallelism with the gripping face of t-heother jaw, and a spring arranged to retain thegripping plate in said recess and to return it to a normal position when the jaws are opened.

2. In a gripper, the combination with a rigid jaw, of a jaw pivoted relatively to the rigid jaw to swing toward the latter through different angles for gripping stocks of different thicknesses, said pivoted jaw having in its inner face a recess the bottom wall of which is concavely curved longitudinally of the jaw, a gripping plate mounted in said recess and movable therein about the axis of said curve into parallelism with the grip ping face'of the other jaw, and a spring plate having one end fitting into a recess in the gripping platefor retaining said plate inthe recess in said jaw and permitting the required movement of sa d plate longitude nally of the jaw. Y

8. In a gripper, the combination with a rigid jaw, of a'jaw pivoted relatively to the rigid aw to swing toward. the latter through ment longitudinally of the jaws by the gripping force to present its gripping face in:

parallelism with the gripping face of the cooperating jaw in the different angular positions of the swinging jaw assumed in gripping stocks of difierent thicknesses.

4. In a gripper, the combination with a rigid jaw, of a jaw pivoted relatively to the rigid jaw to swing toward the latter through different angles for gripping different thicknesses of material, one of said jaws comprising a gripping member mounted to move bodily lengthwise of said aw into different angularrelations to the other jaw in response to pressure upon the material to equalize the pressure between the inner and the outer portions of the gripping faces of the jaws in different angular relations of the jaws.

5. In a gripper, a jaw, a cooperating jaw movable relatively to said first aw into position to grip stocks of different thicknesses, and a gripper plate associated with one of said jaws constructed and arranged to grip the stock with increasing force at the outer portions of the gripping faces of the jaws in response to strain tending to pull the stock out of the gripper.

6. In a gripper, a jaw, a cooperating pivoted jaw having in its face adjacent to the first jaw a recess the bottom wall of which is concavely culwed longitudinally of the aw, and a gripping plate seated in said recess and movable in the direction of the curvature of the recess to bite the upper material with increasing force at the outer portions of the gripping faces of the jaws in response to strain tending to pull the upper material out of the gripper.

7. A gripper having, in combination, a pair of jaws mounted for relative movement into position to grip material between them, one of said jaws having a recess in its inner face and a gripping member mounted in said recess for bodily adjustment angularly relatively to the other jaw in response to engagement with the material, and spring means arranged to oppose yieldingly adj ust ing movement of said member by pressure directed toward said recess and to return the member to a normal position when the gripper releases its hold upon the material.

v8. A gripper having, in combination, a pair of jaws mounted for relative movement into position to grip material between them, one of said jaws having a recess therein to provide a concavely curved bearing and a .stantially at 'WlllCll the gripping face of the member is gripping member mounted in said recess for angular adjustment on said bearing relatively to the other jaw in response to en gagement' with the material, and a resilient plate arranged to press upon said member to determine a normal position of the memher on its bearing while permitting the adjusting movement of the member to take place against the tension of said plate.

9. A gripper having, in combination, a pair of jaws mounted for relative swinging movement into position to grip material between them, one of said jaws having a recess in that face which is opposite to the other jaw to provide a bearing curved substantially about an axis extending laterally of the gripper, and a gripping member mounted on said bearing for adjustment relatively to the other jaw about said axis in response to engagement with the material.

10. A gripper having, in combination, a pair of jaws mounted for relative movement into position to grip material between them, one of said jaws having a recess therein to provide a bearing concavely curved lengthwise of the gripper and a gripping member mounted on said bearing for movement into different angular relations to the other jaw, the axis of curvature of said bearing being located substantially at that side of said member upon which the gripping face of the member is located to cause the outer edge portion of the member to bite the material with increasing force in response to relative pull between the gripper and the material lengthwise of the gr pper.

11. A gripper having, in combination, a pair of jaws mounted for relative swinging movement into position to grip material between them, one of said jaws having a recess therein to provide a' bearing concavely curved about an axis substantially parallel to the aXis of relative movement of the jaws and a gripping member mounted on said bearing for adjustment into diflerent angular relations to the other jaw'in response to engagement with the material, the axis of curvature of said bearing being located subthat side of said member upon located.

12. A gripper comprising a pair of jaws relatively movable to grip material between them, one of said jaws comprising a gripping member and a bearing for said member on which the member is movable bodily lengthwise of said jaw, said bearing being constructed to cause the member to be forced toward the other jaw in response to pull of the gripper upon the material in such direction as to increase the bite of the jaws upon that portion of the material which is engaged by the outer edge of said member.

13. A gripper comprising a pair of jaws relatively movable to grip material between recessto-be forced bysaid inelined wall to them and movable also to pull the material, Ward *the Other in response to the pull one of said jaws being provided with a reilpon thematerial.

cess the bottom Wall of which is inclined to In =testim0ny whereof I have signed my 10 5 the direction of the pull of the gripper and name to thisspecification.

having a gripping member mounted in said CHARLES FAWCETTBENNION.

Copies of this patent may be obtained for five cents each, by addressing the flemmissioner of Tatents, Washington, 1):.0. 

